The price of the silvery-white metal, used in cars’ catalytic converters to limit harmful emissions, soared 270 per cent over five years to a record high above $2,800 a troy ounce in February. The number of catalytic converter thefts in London jumped to 8,248 last year, from 1,674 a year earlier.

The year began with expectations that demand for palladium would outstrip supply by more than 1m ounces. But today, leading producers and consultants are forecasting a market with a much closer match between supply and demand. Over the past few years, carmakers in Europe and China have increased the amount of metal they use in their catalytic converters in order to meet stricter emissions limits.

Carmakers can also replace palladium with platinum, but this is not easy to do without compromising the performance of the catalytic converter. In March, German chemical giant BASF said it had developed a new catalytic converter technology that enabled “partial substitution” of palladium with platinum, but still enabled carmakers to meet more stringent standards on emissions.